land and sea breezes
In coastal areas during the warm summer months:
land surface is heated more intensely during the daylight hours, than an adjacent body of water is heated.
As a result, the air above the land surface heats, expands, and rises, creating an area of lower pressure. At night the reverse takes place.
In mountainous regions during daylight hours:
The air along the slopes of the mountains is heated more intensely than the air at the same elevation over the valley floor.
Because this warmer air on the mountain slopes is less dense, it glides up along the slope and generates a valley breeze.
After sunset the pattern may reverse.
El Niño is the name given to the periodic warming of the ocean that occurs in the central and eastern Pacific.
At irregular intervals of three to seven years, these warm countercurrents become unusually strong and replace normally cold offshore waters with warm equatorial waters.
A major El Niño episode can cause extreme weather in many parts of the world.
What is La Niña? When surface temperatures in the eastern Pacific are colder than average, a La Niña event is triggered that has a distinctive set of weather patterns.